Class Cyanoprokaryota Komárek & Golubić 1990 nom. nud. - cyanoprokaryotes Subclass Nostocophycidae Hoffmann, Komárek & Kaštovský (2005), nom. inval. [monotypic] Order Nostocales Borzì (1914) see Order Nostocales corrig. Borzì 1914 Family Microchaetaceae Lemmermann (1907) see Family Rivulariaceae Frank (1886) Form genus Hassallia M.J. Berkeley ex Bornet & Flahault (1886), nom. illeg. see Genus Tolypothrix Kützing ex Bornet and Flahault 1886